Fight This Weekend

Well i've been i a couple of fights but this weekend i saw something that really made me mad and disapointed. A good friend of mine got into a fight, well it was more like the kicked someone's ***. I guess that guy poked his wife on facebook and he was heated. Well he came over to my niece's birthday and the other guy showed up. He brought his girlfriend and son with him. My friend beat the crap out of this guy while his 5 yr old son watched. It pissed me off even more was no one wanted to stop it. I was the only one who was holding back my friend, and he's a bigger guy, musclar and tall. Everyone else was just watching. At first i didn't know what to do, should i try to stop him or take the other man's kid away from the scene... i really couldn't believe that no one else did anything to try to stop it, my older brother and cousin jumped in to try to stop it but by then it was already over. Why do people do stupid stuff like this, and in front of a little kid. i feel so bad for all three of them, the guy, his kid, and his girlfriend. i looked into her eyes and she was terrified and shocked. those eyse will probably haunt me for life...